Accumulator



March 7, 1944. A, L, PARKER 2,343,320

ACCUMULATOR Filed March` 1a, 1940 m .Z RC, l

Z? f4 A Z0 20 357] 0 n ggf* y JJ I@ Patented Mar. 7, 1944 ACCUMULATOR Arthur L. Parker, Cleveland, Ohio, assignor to The Parker Appliance Company, Cleveland, Ohio, a corporation of Ohio Application March 18, 1940, Serial No. 324,720

(Cl. 13S-30) 4 Claims.

The present invention relates to new and useful improvements in pressure accumulatore or condensers, and more particularly to improvements in an accumulator which is adapted to be employed in iiuid pressure systems.

In various types of iiuid pressure systems, it is desirable to employ an accumulator. In general, such an accumulator consists of a casing within which is secured a flexible diaphragm member. This diaphragm divides the casing into two chambers or compartments, each of which communicates with a separate uid pressure line. One of the compartments is in communication with the main fluid or hydraulic pressure line, and the other compartment is in communication with another pressure line, preferably a compressed air line. The purpose of the accumulator is to store up a reserve supply of fluid under pressure which is adapted to gain access to the main pressure delivery line when needed.

An accumulator of this type may be employed for augmenting the work of a pump in a :fluid pressure system under certain conditions. Thus, where there are two or more hydraulic units to be operated by a single pump, fluid is pumped from a reservoir and delivered to the main delivery line which supplies the uid to each hydraulic unit. This main delivery line is also connected to one of the compartments of the accumulator, and the other compartmentI of the accumulator may be connected to a compressed air line. Where several hydraulic units are to be operated at the same time, the pump may not be able to deliver sumcient fluid under pressure to all of the units, and in this case, the accumulator serves to force additional fluid under pressure back into the main delivery line as soon as the pressure in the main line drops a predetermined amount. Similarly, where a fluid pressure system is subjected to pulsating pressure surges, the accumulator serves to check the drop in pressure and to maintain the pressure more constant. Then again, the accumulator may be employed to directly operate a hydraulic unit, in which case the pump may be connected so that it will build up pressure in one compartment of the accumulator to a certain point and then be cut out until the pressure in this compartment of the accumulator has dropped a predetermined amount. There are various types of installations in which accumulators may be employed, but such accumulators are particularly adapted for use with the iiuid pressure systems of aircraft or the like.

An object of the present invention is to provide an improved and eicient sealed connection between the casing and the diaphragm which divides the casing into separate compartments or chambers.

A further object of the invention is to provide a connection between the casing and the diaphragm wherein the fluid under pressure within the casing tends to more tightly seal the connection between the diaphragm and the casing so as to prevent leakage.

A further object of the invention is to provide an accumulator of the above type, wherein the diaphragm has an enlarged annular beaded edge which is adapted to be tightly clamped between similarly shaped parts of the casing, and wherein means are provided for limiting the clamping movement between the parts.

A still further object of the invention is to provide an accumulator wherein the casing is formed of separate sections suitably shaped to receive the enlarged or beaded edge of the diaphragm, and wherein means are provided for limiting the clamping movement of the parts of the casing so as to prevent undue compression of the edge of the diaphragm.

A still further object of the invention is to provide a novel form of diaphragm for the accumulator, wherein the diaphragm normally assumes a pleated or corrugated intermediate position so that movement thereof one way or the other under the inuence of fiuid under pressure will not stretch the diaphragm, nor will it tend to pull the diaphragm from its connection with the casing.

The above and other objects of the invention will in part be obvious and will be hereinafter more fully pointed out.

In the accompanying drawing,

Figure 1 is a side view, partly in section, showing the assembled accumulator with the diaphragm in an intermediate position,

Figure 2 is a similar side view, partly in section, showing the assembled accumulator with the diaphragm extended into contact with one inner face of the casing.

Figure 3 is an enlarged fragmentary side view, in section, showing the formation of the edge of the diaphragm and the cooperating parts of the casing before the parts are clamped tightly together.

Figure 4 is a sectional view, taken along the line 4-d of Figure 1, showing the ribbed er corrugated construction of the casing.

Figure 5 is a fragmentary side view, in section, showing a modified form of diaphragm with additional means for maintaining a iluid tight joint.

Figure 6 is a fragmentary side view, in section, showing a modified form oi diaphragm ein ployed with a modified construction of casing.

Figure '7 is a fragmentary side View, in section, showing a further modified form of casing.

One form of the invention is shown in Figures l through 4 of the accompanying drawing. The accumulator casing is illustrated as being spherical, but it is to be clearly understood that the shape of the casing may be altered, if required. The casing is illustrated as including a pair of semi-spherical members I0, Ilia which are substantially identical. These casing members Iii, Ida may be formed from stamped sheet metal, and are provided with ribs II, IIa for strengthening and reinforcing purposes. The casing member Il] is provided with an outwardly extending annular skirt portion 62 which defines an opening therein, and the casing member lila is provided with a similar skirt portion i2. Adapters I3, i3d are suitably secured to the portions I2, I2a, respectively, as by welding or the like. These adapters are illustrated as being internally threaded for receiving suitable conduits. The accumulator casing is divided by a diaphragm I4 into separate compartments or chambers I5, I5a so that the adapter ISS is in communication with the chamber I5, and the adapter Ita. is in communication with the chamer I5a.

The annular edge portions of the casing members I, lila, are similarly shaped, as particularly shown in Figure 3. The edge portion I5 of the casing member I extends outwardly therefrom and is shaped to provide an inner concave surface and an outer convex surface. The edge portion I6 merges into the casing member Ill in such a manner as to provide a depending lip I'I. The edge portion Iba of the casing member Illa is similarly and oppositely shaped to provide an inner concave surface and an outer convex surface and an upstanding lip Ila which is opposed to the lip Il' on the casing member Ill. The edge portions I'o, Ilia. are also opposed to one another and form therebetween a recess within which the enlarged beaded edge I8 of the diaphragm I is disposed. This beaded edge it of the diaphragm is provided with a recessed portion I9 at the outer edge thereof between the opposed ends 2G, Elia of the edge portions I5, iba, respectively. The parts are shown separated in Figure 3, that is, before the casing members are clamped together. In order to clamp the casing members il), Illa together and to effect a tight seal between the diaphragm and the casing members, male and female clamping members 2|, 22, respectively, are employed. These clamping members have threaded engagement with one another. The inner surface 2Ial of the male clamping member ZI is shaped to provide a concave surface into which the outer convex surface of the edge portion Ia is adapted to fit. The male clamping member is also provided with a shoulder portion 2lb which fits snugly within the recess provided by the lip I'Ia. The inner surface 22a of the female clamping member 22 is also shaped to provide a concave surface' into which the outer convex surface of the edge portion I6 is adapted to snugly fit. rfhe female clamping member 22 is also provided with a shoulder portion 22h which snugly fits within the recess provided by the lip I7.

When the clamping members are placed Vin engagement with the edge portions i5, Ilia of the casing members Ill, Illa, and threaded into one another, the casing members will be drawn together from the separated position of Figure 3 to the clamped position of Figures 1 and 2. During this clamping movement the bead I8 of the diaphragm I4 is deformed so as to entirely dll the recess provided between the edge portions I6, I ta. The diaphragm is preferably made from some form of material which is deformable but substantially noncompressible so that the recess I9 in the bead is lled by movement of the bead during the clamping action. This recess in the bead serves to prevent the material thereof from being forced outwardly between the edges 20, 2da of the edge portion I9, Ita, respectively. The edges 263, 26a abut against one another when the parts are tightly clamped and thus serve as a limiting means for preventing undue compression of the diaphragm. However, the clamping of the beadv I8 on the diaphragm serves to completely seal the joint between the casing members I0, Illa., and the lips I'i, Ila also become slightly imbedded in the narrow portion of the diaphragm within the bead I8. The abutting edges 2i), 2da also serve to prevent the lips Il, IIa from compressing the diaphragm too tightly. There is thus provided an eiicient fluid seal, and any fluid under pressure which tends to leak between the diaphragm and the lips I'! or I'Ial will simply tend to force the bead IBa outwardly into tighter YKsealing contact with the edge portions iS, Ita so that the fluid under pressure in the chambers Iii or Ia will serve to more tightly seal the connection between the diaphragm and the casing. rihe large bead I8 on the diaphragm ILS not only serves as a fluid sealing means, but also as an anchoring means cooperating with the edge portions of the casing members to firmly secure the diaphragm to the casing members.

The diaphragm I4, as indicated above, is preferably formed of a material which is flexible and deformable, but substantially noncompressible. Preferably, the diaphragm is moulded in its orig inal form to normally assume the position shown in Figure l wherein there are a plurality of annular pleats or corrugations 23. Thus, when the diaphragm is extended one way or the other within the accumulator casing, the pleats 23 are unfolded to permit the diaphragm to assume the position shown in Figure 2 wherein it is substantially in contact with one of the casing members. The pleated form of the diaphragm permits this movement without any stretching of the diaphragm so that no pulling force will be exerted on the connection between the diaphragm and the casing. The central portion of the diaphragm may be provided with some form of reinforcing means to prevent the diaphragm from being forced through one of the openings in the adapters I3, l3a. As illustrated, washers 2li are secured on opposite sides of the diaphragm by a pin or rivet 25. One of the washers will thus engage the inner edge of one of the adapters to prevent the diaphragm from being blownthr'ough the opening. The diaphragm may be originally formed with a single washer moulded within the body thereof in this central region, or the adapters may be formed with a plurality of small openings Aso that the diaphragm will not be forced therethrough.

In using the accumulator, the chamber I5a may be connected through the adapter I3a to the Working uid line which may be a hydraulic pressure line. The chamber I may be connected through the adapter I3 with a compressed air line.vv When the pressure of the hydraulic or working fiuid is built up, the diaphragm I4 will tend to assume the position shown in Figure 2, thus enlarging the chamber I5a and reducing the size of the air chamber I5. sure of the working iiuid drops, the air pressure operating in the chamber I5 will tend to force the diaphragm I4 downwardly so as to force the working fluid in the chamber I5a into the hydraulic pressure line. Thus, the pressure of the fluid `in the hydraulic line can be maintained substantially constant for various purposes which have been previously mentioned above.

In Figure 5, there is shown a modified form of diaphragm and sealing means. In this form of the invention, the diaphragm Mais provided with pleats 23a and with an enlarged bead I8a which is clamped between theedge portions I6, Ilia of the casing members rI Il, Illa, respectively by means of the clamping members 2 I, 22 in the same manner as pointed out above. The diaphragm Ida is provided with oppositely extending flange portions 26, 26a which contact with the adjacent inner surface of the easing members III, Illa, respectively. 'Ihese flange portions 26, 26a serve as an additional sealing means for preventing leakage of the fluid, and split resilient rings 21, 27a are employed for maintaining the flange portions 26, 26a in tight contact with the inner surface of the sealing members. Thus, the fiuid under pressure in both compartments of the casing and also the resilient rings serve to maintain the fiange portions of the diaphragm in tight sealing contact with the sealing members.

In Figure 6, there is shown a modified form of the accumulator` casing. In this form of the invention, the casing members 28, 28a are formed of machined parts and not from stamped sheet metal, as illustrated in connection with Figures 1 through 5. The casing member 28 is shaped to provided a depending internally threaded skirt portion 2S which threadedly engages a male portion 30 ing members may be turned relative to one another to effect the clamping of the diaphragm. The casing member 28 is provided with a recessed portion 3|, and the casing member 28a is provided with a recessed portion 32, these recessed portions opposing one another and serving to house the enlarged beaded edge I8b on the diaphragm Illb. The portions 29, 30 on the casing members are shaped to provide abutting shoulders 32 which serve to limit movement of the casing members toward one another. The casing members are also provided with opposed annular lips or shoulder lportions 33, 33a which serve to clamp the diaphragm. In Figure 7, there is shown a further modification of the form of the invention shown in Figure 6. In this form of the invention, the casing members 34, 34a are provided With outwardly extending shoulder portions 35, 35a abut against one another and serve to to receive locking bolts 36. The shoulder portions 35, 25a abut against one another and serve to limit movement of the casing members toward one another.

From the foregoing description, it will be seen that the present invention provides a highly efcient form of accumulator wherein an enlarged beaded portion on the diaphragm is securely anchored between suitably shaped parts of the casing members. The anchoring bead on the dia- Thus, when the preson the casing member 28a. Thus, the casphragm also serves as a iiuid seal when compressed by movement of the casing members toward one another. This clamping movement of the casing members is limited by shoulder means so that the diaphragm will not be unduly compressed and damaged.

It is to be clearly understood that various .changes in details of construction and arrangement of parts may be made without departing from the scope of the invention as set forth in the appended claims.

I claim:

1. An accumulator comprising a pair of members defining a casing and having edge portions shaped to provide opposed recesses, a diaphragm extending across the casing and having around the edge thereof an enlarged annular bead disposed between the edge portions of said members, clamping means for effecting movement of said members toward one another whereby to clamp the said bead, and means providing annular flange portions on the diaphragm and disposed within the casing and abutting against the inner surfaces of the said members whereby to provide an additional fluid seal.

2. An accumulator comprising a pair of members defining a casing and having edge portions shaped to provide opposed recesses, a diaphragm extending across the casing and having around the edge thereof an enlarged annular bead disposed between the edge portions of said member, clamping means for effecting movement of said members toward one another whereby to clamp the said bead, means providing annular fiange portions on said diaphragm disposed within the casing and abutting against the inner surfaces of said members whereby to provide an additional fluid seal, and resilient split rings contacting with the inner surfaces of said flange portions and serving to force the said ange portions outwardly into tight contact with the said members.

3. An accumulator comprising a pair of sheet metal semi-spherical casing members having the edge portions thereof turned outwardly and shaped to provide opposed recesses and position the edges so that they are adapted to be placed in abutted relation, said outwardly turned portions where they join the casing members being spaced from each other when said edges are abutted to provide an entrance to the opposed recesses of less width than the maximum distance between said opposed outwardly turned portions, a diaphragm extending across the casing and 1 having around the edge thereof an enlarged annular -bead disposed within the opposed recesses in the outwardly turned portions and dimensioned so as to be compressed by said portions when the edges are in abutted contact, and clamping rings recessed to receive said outwardly turned edge portions of the casing and adapted to secure the casing members together with the edges in abutted contact.

4. An accumulator comprising a pair of sheet metal semi-spherical casing members having the edge portions thereof the edges so that they are adapted to be placed in abutted relation, said outwardly turned portions where they join the casing members being spaced from each other when said edges are abutted to provide an entrance to the opposed recesses of less width than the maximum distance between said opposed outwardly turned portions, a diaphragm extending across the casing and iiaving'around the edge thereof an en.- projecting said bead between the edges when larged annular bead disposed within the opposed compressed by the projecting members, and recesses in the outwardly turned portions and clamping rings recessed to receive said outwarddimensioned so as to be compressed by said por- 1y turned edge portions of the casing and adapted tions when the edges are in abutted contact, the to secure the casing members together with the portion of the bead adjacent the meeting abutted edges in abutted contact. edges of the casing being cut away so as to a-Void ARTHUR L. PARKER. 

